Associations of Echocardiography Markers and Vascular Brain Lesions: The ARIC Study

Heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) accounts for nearly half of all heart failure cases and has a prevalence that is expected to rise with the growing ageing population. HFpEF is associated with significant morbidity and mortality. Specific HFpEF risk factors include age, diabetes, hypertension, obesity and atrial fibrillation. Haemodynamic contributions to HFpEF include changes in left ventricular structure, diastolic and systolic dysfunction, left atrial myopathy, pulmonary hypertension, right ventricular dysfunction, chronotropic incompetence, and vascular dysfunction. Inflammation, fibrosis, impaired nitric oxide signalling, sarcomere dysfunction, and mitochondrial and metabolic defects contribute to the cellular and molecular changes observed in HFpEF. HFpEF impacts multiple organ systems beyond the heart, including the skeletal muscle, peripheral vasculature, lungs, kidneys and brain. The diagnosis of HFpEF can be made in individuals with signs and symptoms of heart failure with abnormality in natriuretic peptide levels or evidence of cardiopulmonary congestion, facilitated by the use of HFpEF risk scores and additional imaging and testing with the exclusion of HFpEF mimics. Management includes initiation of guideline-directed medical therapy and management of comorbidities. Given the significant impact of HFpEF on quality of life, future research efforts should include a particular focus on how patients can live better with this disease.

MRI Investigation of the Association of Left Atrial and Left Atrial Appendage Hemodynamics with Silent Brain Infarction

BACKGROUND

Left atrial (LA) myopathy is thought to be associated with silent brain infarctions (SBI) through changes in blood flow hemodynamics leading to thrombogenesis. 4D-flow MRI enables in-vivo hemodynamic quantification in the left atrium (LA) and LA appendage (LAA).

PURPOSE

To determine whether LA and LAA hemodynamic and volumetric parameters are associated with SBI.

STUDY TYPE

Prospective observational study.

POPULATION

A single-site cohort of 125 Participants of the multiethnic study of atherosclerosis (MESA), mean age: 72.3 ± 7.2 years, 56 men.

FIELD STRENGTH/SEQUENCE

1.5T. Cardiac MRI: Cine balanced steady state free precession (bSSFP) and 4D-flow sequences. Brain MRI: T1- and T2-weighted SE and FLAIR.

ASSESSMENT

Presence of SBI was determined from brain MRI by neuroradiologists according to routine diagnostic criteria in all participants without a history of stroke based on the MESA database. Minimum and maximum LA volumes and ejection fraction were calculated from bSSFP data. Blood stasis (% of voxels <10 cm/sec) and peak velocity (cm/sec) in the LA and LAA were assessed by a radiologist using an established 4D-flow workflow.

STATISTICAL TESTS

Student's t test, Mann-Whitney U test, one-way ANOVA, chi-square test. Multivariable stepwise logistic regression with automatic forward and backward selection. Significance level P < 0.05.

RESULTS

26 (20.8%) had at least one SBI. After Bonferroni correction, participants with SBI were significantly older and had significantly lower peak velocities in the LAA. In multivariable analyses, age (per 10-years) (odds ratio (OR) = 1.99 (95% confidence interval (CI): 1.30-3.04)) and LAA peak velocity (per cm/sec) (OR = 0.87 (95% CI: 0.81-0.93)) were significantly associated with SBI.

CONCLUSION

Older age and lower LAA peak velocity were associated with SBI in multivariable analyses whereas volumetric-based measures from cardiac MRI or cardiovascular risk factors were not. Cardiac 4D-flow MRI showed potential to serve as a novel imaging marker for SBI.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

Left ventricular hypertrophy as a risk factor for accelerated brain aging: Results from the Study of Health in Pomerania

Previous studies provided evidence for the importance of cardiac structure abnormalities, in particular greater left ventricular (LV) mass, for brain aging, but longitudinal studies are lacking to date. We included 926 individuals (median age 48 years; 53% women) from the TREND cohort of the Study of Health in Pomerania (SHIP) without reduced ejection fraction or a history of myocardial infarction. LV mass index (LVMI) was determined by echocardiography at baseline. Brain morphometric measurements were derived from magnetic resonance images at baseline and 7-year follow-up. Direct effects of baseline LVMI on brain morphometry at follow-up were estimated using linear regression models with adjustment for baseline brain morphometry. At baseline, median LVMI was 40 g/m2.7 and 241 individuals (26%) met the criterion of LV hypertrophy. After correction for multiple testing, baseline LVMI was directly associated with reduced global cortical thickness and increased cortical brain age at follow-up independent from hypertension and blood pressure. Exposure-outcome relations were nonlinear and significantly stronger in the upper half of the exposure distribution. Specifically, an increase in baseline LVMI from the 50% quantile to the 95% quantile was associated additional 2.7 years (95% confidence interval = [1.5 years, 3.8 years]) of cortical brain age at follow-up. Additional regional analyses yielded bilateral effects on multiple frontal cortical regions. Our findings highlight the role of cardiac structure in brain aging. LVMI constitutes an easily measurable marker that might help to identify persons at risk for cognitive impairment and dementia.

Echocardiographic correlates of MRI imaging markers of cerebral small-vessel disease in patients with atrial-fibrillation-related ischemic stroke

Background and objectives

Atrial fibrillation (AF) has been linked to dementia risk, partly explained by cerebral small vessel disease (CSVD). Since AF and cardiovascular comorbidities were associated with cardiac dysfunction, we aimed to determine the association between echocardiographic parameters and neuroimaging markers of CSVD in patients with AF-related ischemic stroke.

Methods

This cross-sectional study enrolled patients with AF-related ischemic stroke from March 2013 to December 2019 who underwent transthoracic echocardiography and brain 3T MRI, including T1, T2, Flair, and SWI imaging sequences. We assessed the presence of lacunes and cerebellar microbleeds (CMBs), the severity of white matter hyperintensity (WMH) scored by the Fazekas scale (0-6), and the severity of enlarged perivascular spaces (EPVS) in basal ganglia (BG) and centrum semiovale (CSO) classified into three categories (0-10, 10-25, and >25). CSVD burden was rated on a 0-to-4 ordinal scale. Generalized linear regression analysis and post hoc comparisons with Bonferroni correction were performed to assess the association between various echocardiographic parameters and these lesions, adjusted for demographics and potential confounders.

Results

119 patients (68.38 ± 12.692 years; male 45.4 %) were included for analysis, of whom 55 (46.2%) had lacunes, 40 (33.6%) had CMBs, and median severity for WMH, BG-EPVS, CSO-EPVS, and CSVD burden were 2 (IQR: 1-3), 1 (IQR: 1-2), 1 (IQR: 0-1), and 1 (IQR: 1-2) respectively. In multivariable, fully adjusted models, left ventricular posterior wall thickness (LVPW) was associated with a higher risk of lacunes (RR 1.899, 95% CI: 1.342-2.686) and CSVD burden (RR = 2.081, 95%CI: 1.562-2.070). Right atrial diameter (RAD) was associated with greater CSO-EPVS (RR = 2.243, 95%CI: 1.234-4.075). No echocardiographic parameters were revealed to be associated with CMBs and WMH.

Conclusion

In patients with AF-related ischemic stroke, LVPW is associated with a higher risk of lacunes and CSVD burden, while RAD was associated with greater CSO-EPVS. Larger studies are required to determine these associations and to elucidate if these associations can help facilitate cognitive evaluation and brain MRI screening.

Cardiac Hypertrophy Is Associated With Advanced Brain Aging in the General Population

Background

Hypertrophy of the left ventricle (LV) has recently been associated with adverse changes of brain structure in older adults, notably increased burden of white matter hyperintensities (WMHs). Whether greater LV size or mass is also related to WMH burden in middle‐aged adults is currently unclear. In addition, its relation with alterations in cortical thickness (CT) has not been studied to date.

Methods and Results

Data from 1602 participants of the population‐based SHIP (Study of Health in Pomerania) with LV ejection fraction >40% and no history of myocardial infarction were included (aged 21–82 years; median age, 49 years; 53% women). Participants underwent both echocardiography and magnetic resonance imaging of the head. Imaging markers of brain aging (ie, CT and WMH volume) were determined from magnetic resonance imaging scans. LV mass and diameter were associated with lower global CT and greater WMH volume, while adjusting for age, sex, body height, fat‐free body mass, and intracranial volume. Moreover, thicknesses of the interventricular septum and posterior wall were also associated with lower global CT. These associations could not be explained by cardiovascular risk factors (including hypertension), inflammatory markers, or sociodemographic factors. Regional analyses showed distinct spatial patterns of lower CT in association with LV diameter and posterior wall thickness.

Conclusions

LV diameter and mass are associated with lower global and regional CT as well as greater WMH burden in the general population. These findings highlight the brain structural underpinnings of the associations of LV hypertrophy with cognitive decline and dementia.

Cardiac Structure and Function Is Associated With Hemispatial Neglect Severity

Background: Hemispatial neglect is a debilitating consequence of right hemispheric ischemic stroke (RIS), with evidence that patient-level factors influence neglect severity. Study objective: Determine if cardiac function is associated with presence and severity of neglect, independent of infarct size.

Methods: Two hundred and eighteen non-demented, RIS with cerebral MRI and echocardiography who completed ≥1 of 4 tests evaluating neglect were included. Age- and sex- adjusted Z-scores defined neglect with severity categorized as no neglect, neglect on one or neglect on ≥2 tests. The dependent variable was presence of neglect (multivariable logistic regression), or neglect severity (multinomial logistic regression). The association with left ventricular (LV) structure/function (independent variable) was evaluated using separate nested adjustment models.

Results: Patients were on average 61 yo (21–95), female (50%), black (53%), with an ejection fraction of 60% (IQR 20–75%). Fifty eight (27%) had neglect. Each 1 cm increase in LV systolic diameter was associated with a higher relative risk of having neglect on two tests compared to those with no neglect (RRR = 1.83, 95% CI 1.01–3.32), but not after adjusting for education and DWI volume (RRR = 1.68, 95% CI 0.89–3.19). Per 1 cm increase in left atrial (LA) diameter, the relative risk of having neglect on 2 tests vs. no neglect was over two times higher (95% CI 1.04–4.77), but lost significance in the final model (RRR = 1.73, 95% CI 0.76–3.94).

Conclusions: We found an association between markers of diastolic dysfunction (enlarging LV, compensatory enlarging LA) and severity of neglect, suggesting that cardiac structure, and function affects not only lesion volume, but also the functional consequences of infarct volume.

Cerebrovascular Disease and Cognitive Outcome in Patients with Cardiac Disease

The pace of understanding cognitive decline and dementia has rapidly accelerated over the past decade, with constantly evolving insights into the vascular contributions to cognitive impairment and dementia (VCID). Notably, more overlap has been discovered in the pathophysiology between what was previously understood to be Alzheimer's disease and VCID, leading to a heightened emphasis on disease prevention through early and aggressive control of vascular risk factors. One particularly vulnerable population may be those with cardiac disease, as they are at risk for cerebrovascular disease, which itself can lead to dementia, and increasing evidence supports cognitive impairment in disease processes such as heart failure and atrial fibrillation, independent of ischemic stroke, suggesting other potential mechanisms. In this article, we review the evidence supporting the relationship between cardiac disease, cerebrovascular disease, and cognitive decline and discuss the ongoing and future research efforts aimed at defining the important relationship between these entities.

Impact of Cardiovascular Hemodynamics on Cognitive Aging

[Figure: see text].

Left Ventricular Hypertrophy and Cerebral Small Vessel Disease: A Systematic Review and Meta-Analysis

Background and Purpose

Left ventricular hypertrophy (LVH) is associated with the risk of stroke and dementia independently of other vascular risk factors, but its association with cerebral small vessel disease (CSVD) remains unknown. Here, we employed a systematic review and meta-analysis to address this gap.

Methods

Following the MOOSE guidelines (PROSPERO protocol: CRD42018110305), we systematically searched the literature for studies exploring the association between LVH or left ventricular (LV) mass, with neuroimaging markers of CSVD (lacunes, white matter hyperintensities [WMHs], cerebral microbleeds [CMBs]). We evaluated risk of bias and pooled association estimates with random-effects meta-analyses.

Results

We identified 31 studies (n=25,562) meeting our eligibility criteria. In meta-analysis, LVH was associated with lacunes and extensive WMHs in studies of the general population (odds ratio [OR]_lacunes, 1.49; 95% confidence interval [CI], 1.12 to 2.00) (OR_WMH, 1.73; 95% CI, 1.38 to 2.17) and studies in high-risk populations (OR_lacunes: 2.39; 95% CI, 1.32 to 4.32) (OR_WMH, 2.01; 95% CI, 1.45 to 2.80). The results remained stable in general population studies adjusting for hypertension and other vascular risk factors, as well as in sub-analyses by LVH assessment method (echocardiography/electrocardiogram), study design (cross-sectional/cohort), and study quality. Across LV morphology patterns, we found gradually increasing ORs for concentric remodelling, eccentric hypertrophy, and concentric hypertrophy, as compared to normal LV geometry. LVH was further associated with CMBs in high-risk population studies.

Conclusions

LVH is associated with neuroimaging markers of CSVD independently of hypertension and other vascular risk factors. Our findings suggest LVH as a novel risk factor for CSVD and highlight the link between subclinical heart and brain damage.

Associations of Echocardiography Markers and Vascular Brain Lesions: The ARIC Study

Background

Associations between subtle changes in cardiac and cerebral structure and function are not well understood, with some studies suggesting that subclinical cardiac changes may be associated with markers of vascular brain insult.

Methods and Results

Data from the ARIC (Atherosclerosis Risk in Communities) Study (5th ARIC visit; 2011‐2013; N=1974) were used to explore relationships between abnormalities of cardiac structure/function and subclinical brain disease and to test specific associations between those cardiac and vascular brain changes that share a common mechanism. In adjusted models white matter hyperintensities were 0.66 cm³ greater (95% confidence interval [CI] 0.08‐1.25) for every 1‐mm increase in left ventricular LV wall thickness and 0.64 cm³ greater (95% CI 0.19‐1.08) for every 10 g/m² increase in LV mass index, both markers of LV structure. Odds of brain infarction also increased with greater LV wall thickness (odds ratio 1.11, 95% CI 1.01‐1.23 per 1 mm) and larger LV mass (odds ratio 1.08, 95% CI 1.00‐1.17 per 10 g/m²). Higher ejection fraction (per 5%), a marker of systolic function, was significantly associated with decreased odds of overall infarct (odds ratio 0.85, 95% CI0.77‐0.95), but not with cortical infarction (odds ratio 0.92, 95% CI0.78‐1.08).

Conclusions

Among elderly participants in a large cohort study, subclinical markers of LV structure and LV systolic dysfunction were associated with increased odds of brain infarction and more white matter hyperintensities, independent of other vascular risk factors. This suggests end‐organ dysfunction occurs in the heart and brain in parallel, with further studies needed to determine causality.